Series Continuity Error / Anime & Manga

• Demon Slayer: Kimetsu no Yaiba: the anime attempted to give a little more detail to Muzan's short flashback of the day he was almost defeated by a legendary slayer, and the setting of the fight seems to be close to a manor in the anime. The manga gave no actual background on their battleground back then, and when the manga eventually shows how and where the battle went, it is revealed Yoriichi and Muzan fought on a bamboo forest with no manor or any house in sight, resulting in the anime teasing a location that would not exist in the manga.
• In Digimon Adventure 02: The Beginning, Ukkomon transplanting his eye into Lui. It's been explicitly stated that Digimon are not flesh and blood life forms, even in the real world, so this should have no chance of actually working.
• Fairy Tail:
  • The Artifact of Doom in the form of an eight-legged castle in the Nirvana arc could only be destroyed if the crystals at the root of each of its legs were destroyed simultaneously. The protagonists just barely manage to scrape together enough people with the strength left to fight so that they can post someone at all six crystals. Lampshaded in the Q&A section by Mirajane, questioning whether it took off the extra legs to move faster.
  • At the end of the Fighting Festival Arc, Fried is seen with short hair after an Important Haircut, yet is seen with back to normal at the start of the very next arc. The only way his hair could have grown back that quickly is if Lucy had summoned Cancer, who can cut and grow people's hair.
• Fist of the North Star has quite a number of continuity snarls as the series went on:
  • When Kenshiro's adoptive brothers were first introduced, Kenshiro initially mentions that none of them are actually blood-related. Later it turns out that the eldest two, Raoh and Toki, are blood-related after all and we are shown the ruins of their childhood home along with the graves of the birth parents. This can be handwaved by the fact that Kenshiro wasn't exactly sure himself. However, it later turns out that none of them were even born in Japan at all, but that the three of them were refugees from the Land of Shura and that Raoh and Toki's mother is buried in a swamp.
  • If the above situation wasn't confusing enough, along comes the prequel Fist of the Blue Sky, which shows that the baby Kenshiro was born in Japan, wait no, now it's China.
  • A more minor error is Toki being consistently shown with white hair during the Shura arc's flashback sequences, all of which are set when Toki and Raoh were still kids. However, the previous four seasons established and maintained the fact that Toki's natural hair color is brown, and it only became white as a result of being exposed to high levels of radiation as an adult. This one could possibly be handwaved as the work of hair dye, assuming that there Shura had any at the time.
• In Freezing, Arnett McMillan is stated to be Swiss. But in the prologue/spinoff manga Freezing: Zero, she is shown to be American.
• Fullmetal Alchemist:
  • An early Fullmetal Alchemist (2003) episode has Alphonse clearly getting kicked into a pool of water. A much, much later episode has his seal getting wet, and Al not dying from it, as a plot point. It's likely the former scene was The Artifact from the manga continuity.
  • In Brotherhood, the human transmutation circle at the start of the story matches the 2003 anime, which is much more ornate compared to the manga; but when Ed draws another human transmutation circle at the end of Brotherhood, this one matches the manga, not the style created for the animes.
• In the second chapter of Ice Revolution, The Rival has clearly seen tomboy Masaki in her girl's uniform yet in the next chapter she continues to view Masaki as a boy.
• K-On! has two instances between its first and second seasons:
  • In the 7th episode of the second season (the third year for all the girls save Azusa, who is a year younger), Azusa is told of Megumi Sokabe, the former Student Council President who by that point graduated, and she doesn't know who she is. However, Megumi appeared as the Student Council President in one scene in the Season 1, episode 11 taking in Ritsu's profuse apologies for missing another deadline. Every member of the band was there, including Azusa. This is due to a Retcon that changed which year Megumi graduated, as indicated by the color of the ribbon she wears depending on which season you're watching.
• May or may not be only in the Animated Adaptation of Kyouran Kazoku Nikki, but Kyouka complains to Ouka that he never told her about something as amazing as Christmas and, more to the point, getting presents. However this comes up after an episode where Ouka and Kyouka were already officially married for one year, which means they somehow skipped another Christmas entirely for this to make sense.
• In the Majikoi! Love Me Seriously! anime, when the villain Tachibana Takae shows up, everyone besides Momo is confused because they don't know who she is. This confusion extends even to Mayuzumi, who beat Takae prior to the events of the original visual novel to become the youngest member of the "Big Four". As one of the few members of the cast who doesn't blatantly disregard pretty much everyone else, it would be fairly odd for her not to remember her.
• A fairly minor but aggravating one, given how they usually make a pretty decent effort to make sure their Techno Babble is consistent, is the EMS-10 Zudah's model number from Mobile Suit Gundam MS Igloo. The Zudah is a Flawed Prototype frontline combat mobile suit, with the E standing for Experimental, but previous Gundam series had established that in the Zeon model numbering scheme EMS stood for Excavation Mobile Suit while prototypes were denoted with the prefix YMS, which doesn't seem to stand for anything (Young Mobile Suit, maybe?) but follows the tradition of the US Air Force using the letter Y to designate experimental aircraft (most notably the experimental flying Wave-Motion Gun known as the YAL-1).
• Another minor one from Gundam happened in Mobile Suit Gundam Wing: Endless Waltz. While the movie retconned the designs of the Gundams, flashbacks to before the beginning of the series showed the Heavyarms and Deathscythe in their final movie forms, even though both machines received a Mid-Season Upgrade (and Deathscythe was explicitly rebuilt from the ground up, and did not have its Active Cloak wings at the time). In addition, Wing Zero's design change removed its Neo-Bird flight mode. The 2010 manga The Glory of Losers, a retelling of the series, patches this over by using the Endless Waltz designs, while ignoring the movie's flashback errors and instead showing redesigned pre-upgrade versions of the suits when appropriate. The manga even restores the TV version of Wing Zero as the original Super Prototype state of that suit, before later being upgraded to the Endless Waltz version.
• Naruto:
  • The most powerful techniques used by an Uchiha depend on the state of their eyes - when Sasuke was going blind due to over-using his Mangyeko techniques, those techniques deteriorated and vanished as a result. However, in the end of the series, Madara continues to use these same techniques despite having no eyeballs whatsoever, frustrating fans who were hoping that this character would get some comeuppance.
  • On fillers going against canon, episode 481 depicted Neji without his curse mark prior to his father's death. The manga however showed that he received it on Hinata's third birthday. The succeeding episode also has an inconsistency with Sakura. It shows Sakura telling Ino that she likes Sasuke when they're alone in her secret hideout, however the manga and previous episodes showed that they were with other girls on the playground when that happened.
  • It was said that Pain killed Hanzo and everyone even remotely associated with him. It is later revealed that Danzo helped Hanzo and he is shown to be alive and well.
  • Boruto implies that Naruto and Hinata's first missions were dangerous. According to Naruto, Naruto's first few missions were simple chores like mowing grass and finding lost pet cats. It wasn't until Naruto asked for a higher level mission that he first went on a dangerous mission (and it was only dangerous because of complications).
  • An anime-only filler depicts a younger version of Kakashi, Obito, and Rin together. However, Kakashi is supposed to be 5-6 years younger than his teammates. He's 6 when he becomes a genin.
  • Anime-only flashbacks depict Naruto playing with Kiba, Shikamaru, and Chouji in the academy. In the manga, Naruto had a Friendless Background and didn't become close to them until after he graduated.
• Nyaruko: Crawling with Love! pointed out one from the original light novels in the first TV series. The short has Mahiro and Nyarko doing a Fourth-Wall Mail Slot, but the only question they take asks why Mahiro's lunch period was placed after third period in the novels and after fourth period in a magazine-published short; Nyarko responds by angrily tearing up the letter.
• Pokémon: The Series:
  • One of the Best Wishes episodes has Ash searching for a Thunderstone as part of a contest scavenger hunt. Someone throws one at him, and Ash is desperate to catch it before it hits Pikachu, yelling that he'll evolve if he touches it. However, Pikachu smacked away the stone Ash had in the first season and didn't evolve as a result.
  • Another season one episode claimed that Pokémon aren't evil, even if they do obey their evil masters. Later seasons features many wild Pokemon who just do asshole things because they're jerks, some of them outright evil, like the Togepi in "Where No Togepi Has Gone Before!", a gang of Litwick in Best Wishes, and the recurring Malamar in XY. Then again, this was said by just one (rather naive) Ekans who can't reasonably be an expert on Pokémon morality, so make of it what you will.
  • Pokéathlons were not a thing when Ash was in Johto, yet in a Sinnoh episode they suddenly show up and Brock acts like they knew all about them all this time.
  • The Beheeyem in a Decolara episode says that "idiots can't be hypnotized" regarding why Ash, Jessie, and James No Sold their hypnotic suggestions. Tell that to Melvin the Stage Magician, a herd of wild Stantler, and Marcus in Ash's case, and Ash's own Noctowl for all three! Heck, Leon and his own Beheeyem from Best Wishes proper could count given that they sent Ash into the same dream state as Iris, Cilan, Pikachu, Meowth, et. al. Ash was effectively a Hypno Fool prior to Decolora.^note Meowth's Fury Swipes were what protected Ash from the Malamar later on; Jessie and James fell prey like everyone else save Meowth, who slapped himself awake.
  • The third episode of the XY series claims that Meowth can't translate electric shocks between Pikachu and Dedenne; but Meowth had no problem doing so between Pikachu and Zapdos in Pokémon 2000.
  • The Japanese ending of the first movie indicates the Team Rocket trio weren't affected by Mewtwo's Laser-Guided Amnesia, due to Mewtwo being unaware they were there, but in Mewtwo Returns they have no memory of the events and Mewtwo recognizes them.
  • Ash being declared to be 10 years old by the narrator at the start of the Best Wishes series is this due to the Movie three short, in both versions, declaring Ash and Pikachu to be celebrating an anniversary of when they first met. Scaled in a year (with some fans arguing if it was the first year or second year due to conflicting sub and dub comments in previous episodes).
  • The anime is rather consistent with implying that Jessie is in her mid-20s. A flashback in the Sinnoh episode "Crossing Paths" is an exception, however, as it implies she's much younger.
• Lampshaded in Pretty Sammy TV Series when Romio appears as the third candidate who was flung into a Trap Door in the beginning. She then starts a Flashback to the first episode and afterwards it's pointed out they look nothing alike.
• Don't try to put Rave Master on a timeline. You just can't. If you were to try, there'd really only be one little flaw in it — Haru claiming that he's been fighting to save the world for two years when he's only been the Rave Master for a little over one.
• Tengen Toppa Gurren Lagann started off with a prologue involving Simon/Kamina waging war against "All the lights in the sky." This is similar to battles late in the series, but never really fits any of them. The producers admitted that this was a fluke on their part, that it was meant to be Shout-Out to Arcadia, and that they never got around to building up to that scene in the main series. This had led fans to suggest that this scene is an alternate universe, a fantasy of Boota, an alternate timeline in which Kamina leads Dai-Gurren into space/Simon is sent back in time to battle the Anti-Spirals as well as become Kamina's father.
• In Urusei Yatsura, it's established early on that Lum's mother cannot speak Japanese, leading to a misunderstanding where she thinks Mendou's mother is hitting on her and wants to marry her. There's at least one episode from later in the show's run that shows her both speaking and understanding Japanese without any difficulty.
• Wandering Son:
  • In the first volume, it's shown that Takatsuki does not know (the then unnamed) Kanako well enough to know of her ditzy qualities. The next volume establishes them as having been friends since kindergarten.
  • Mako acts surprised when Nitori tells her she has a part-time job yet earlier Nitori clearly told her, and she even imagined what she'd look as a waiter.

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